Product introduction

At present the composite pipe has been widely used in many applications and various steel-plastic composite pipes have been developed. The Steel Reinforced Polyethylene Spiral Corrugated Pipe (SRPCP pipe) is one of the best solutions among those pipes, which has been researched by Goldstone company with Chinese patent. It is a great technical innovation to use the steel-plastic composite construction instead of the single material (plastic) for sewage and drain pipe system. The new composed structure brings many advantages like higher stiffness, less weight, low cost, large diameter, etc.

The diameter of the pipe is from 300 mm (12 inch) up to 3200 mm (126 inch). The obvious advantage of the new composite pipe is the high stiffness and low cost if compared with the universal buried plastic sewage pipe. The ring stiffness reached SN8 to SN16, which is a surprise value for other plastic pipes. This pipe meets ASTM 2435-12 standard and Israel, Italian standard, Chinese national standard etc.

The elastic modulus of carbon steel is almost 200 times higher than polyethylene; its value is about 190,000 Mpa however the polyethylene is around 800Mpa only. So if we can combine the advantages of both steel and plastic, that will be an ideal method to get a perfect pipe with high stiffness and less cost. The question is how to compose two kinds of material in a good way, keep their benefits but avoid the defects, to let them complement each other. There are many manufacturers are researching the answer of this question, among them, the Chinese SRPCP pipe is absolutely a relative nice and successful solution for the composite pipe proved by mass evidences since 2003.

From the diagram we know that the main pipe body of MRP is formed by the HDPE layer (inner and outer layer), and V-shape steel band which pre-coated with adhesive resin on the surface undertakes the primary support of the pipe; the steel and HDPE is wrapped on the mandrel and bond together to be one integrated spiral-corrugated pipe. Thereby, this new pipe collects advantages from different materials organically, high rigidity and strength of steel; anticorrosive, wear proof properties and flexible of plastics.

Advantages of the reinforced pipe

Reinforced by high strength steel band, high stiffness SN8 to SN16 by ISO 9969

Diameter range: DN300 – DN3000 mm

High ring stiffness

For normal buried sewage plastic structure wall pipe, its maximum ring stiffness is difficult to over SN8. But in new pipe, stiffness can easily reach the surprisingly value of SN8, SN12.5 and SN16, even higher if necessary. In other hand, thanks to plastic properties, the plastic-steel-plastic composite structure could against corrosion very well. Therefore, this composite corrosive-proof pipe could be applied under different kinds of hard conditions. For example, at some coastal areas, due to the soil contains corrosive substance, the concrete pipe will be invalid after a short service time; then the users hope to have a kind of plastic sewage pipe with outstanding anti-corrosive property. But in the past, there is no such high ring stiffness plastic pipe could be selected, and now the new composite plastic pipe gives them a good solution.

Besides the enhanced performance, the other primary advantage is that the new pipe can save material cost obviously. In general it will be thinking as a great improvement if any technique innovation could reduce the material consumption in 10%. However, the steel reinforced polyethylene spiral corrugated pipe has saved the plastic consumption nearly in 50% when compared with other plastic sewage pipe in same diameter and ring stiffness. It is an exciting value for production cost reducing.

The reason is that the elastic modulus of carbon steel is 200 times higher than polyethylene. When the thin steel band is formed into the reinforced rib of the pipe, the ring stiffness contributed by it will be far over than the effect of a very thick polyethylene structure layer. The composite pipe can obtain the desired stiffness easily by adjusting the thickness of steel band and the height of steel rib. In MRP pipe, polyethylene is just provide a corrosion protection and anti-abrasion effect, thus, the amount of polyethylene is not too much, as well the steel rib material because the stiffness is already high enough.

The polyethylene weight of the composite pipe is only 2/3 of the full plastic pipe; this is a very valuable solution to reduce the material cost under the situation of the plastic price continuous raising.

Connection System

This pipe system provides different connecting method to match the varied demand of credible sealing and convenient installation preferably. As well, the MRP pipe has many properties relative to other plastic drain pipe, such as reliable water sealing, long service life, flexible and earthquake-proof, less weight, easy and fast installation, etc.